Speaker Model
Where does the speaker gets its initial energy to work?
An energy source like a computer or phone
This object has two poles
What is a magnet?
This is a coil of wire with a current running through it
An electromagnet
What is an electromagnet?
An electromagnet is a magnet that relies on electricity to generate a magnetic field.
When two magnets have repulsive forces on them and they are pushed together and then released, _____________ energy is transferred to each magnet as they move back apart.
Kinetic
Where does the electric energy from the computer/phone go?
It travels through the wires and into the coils.
A compass will always point in this direction if there is no magnetic field around it
What is North?
How do you change the direction of the electric current in a circuit?
Flip the battery
In this device, electricity is supplied, causing a magnetic field that causes motion
What is a motor?
When two magnets have attractive forces between them and they are pulled apart and then released, _______________ energy is transferred to each magnet as they move back together.
Kinetic
Does the permanent magnet cause the coil of wire to become an electromagnet? Explain
No it pushes/pulls on the electromagnet, the electric current caused the wire to become an electromagnet.
A magnetic field always travels in this direction
What is North to South?
Adding more batteries to a circuit causes a light to be brighter, why is that?
Adding more batteries transfers more energy, and results in stronger forces
In a junkyard they use an electromagnet to move the cars, how do they get the electromagnet to let go of the car?
They turn off the energy source
When you increase the distance between two magnets and they still connect what form of energy did you increase?
Potential energy
The electromagnet changes current and this changes the direction of the poles. What happens between the electromagnet and the permanent magnet as the electromagnet changes current back and forth?
Changing the current will alternately produce force pairs between the magnet and the coil of wire that push them apart (repulsive force) and pull them together (attractive force).
This substance can help detect a magnetic field
What are iron filings?
How do you flip the poles in an electromagnet without moving it?
Flip the current that it receives.
In an electric car there is a coil of wire attached to a metal rod. What happens when the coil of wire spins?
It spins the gears that spin the wheels of the car.
When you decrease the space between magnets does the magnetic force become stronger or weaker? Why?
It gets stronger because the magnets are further into each other's magnetic fields and the magnetic fields are stronger.
What causes the speaker to vibrate finally?
When the direction of the electric forces change the coil (and the attached speaker cone) will move back and forth (vibrate).
How can you decrease the strength of a magnetic field?
Answers will vary
Objects that can become magnetic are called:
ferromagnetic
How does the Maglev train levitate?
Magnets attached to the bottom of a Maglev Train are repelled by the magnetic field of electromagnets attached to the rails below.
Name three forms of energy that are associated with how the speaker works:
Thermal energy, kinetic energy, potential energy, magnetic energy